Climate & Weather Guide in Guinea-Bissau

Climate zones, seasonal temperatures, rainfall patterns, and best travel times

Guinea-Bissau has a hot tropical climate shaped by the Atlantic coast, mangrove estuaries, and a strong wet-dry seasonal cycle. Most of the country falls under tropical savanna climate (Aw), with a rainy season from roughly May or June to October or November and a dry season dominated by the harmattan in winter. Coastal areas are more humid and wetter than the inland east, while temperatures stay warm year-round with only small seasonal variation. Recent climate assessments indicate rising temperatures and a gradual decline in rainfall over recent decades, which matters for water supply, agriculture, and flood risk for residents and expats alike.

Summer Average

26-31°C

Winter Average

23-27°C

Climate Types

Tropical savanna and Coastal tropical humid

Annual Rainfall

1000-2500 mm

Sunshine Hours

2,400-3,000 hrs/yr

Average Humidity

70-85%

Regional Climate Variations

Bissau and Coastal Mangrove Belt

This western coastal zone is the wettest and most humid part of the country, influenced by the Atlantic Ocean, mangroves, and river estuaries. Rainfall is abundant in the wet season, and the air often feels sticky because of high humidity. Temperatures remain warm all year, but coastal breezes slightly soften the heat compared with the inland east. The rainy season can bring flooding and difficult travel, while the dry season is sunnier and more comfortable for daily routines.

Summer:26-30°C

Winter:23-26°C

High rainfall

Warm, humid, and seasonally rainy, with a heavy monsoon feel from late spring to autumn and a milder, dusty dry season in winter.

Central Rice Plains and River Valleys

The central belt has a classic tropical wet-and-dry pattern, with a long rainy season that supports rice farming and a pronounced dry season when dustier continental air arrives. Conditions are still warm throughout the year, but this zone tends to feel slightly less humid than the coast outside the wettest months. Seasonal flooding can occur in low-lying farmland, while the dry months are more practical for outdoor work, travel, and construction. This is one of the most representative areas for understanding everyday life in Guinea-Bissau.

Summer:27-32°C

Winter:22-26°C

High rainfall

Hot and seasonally wet, with a clear divide between lush monsoon months and a drier, sunnier winter period.

Eastern Savannah and Borderlands

The eastern interior near the borders with Guinea and Senegal is generally a little hotter and drier than the coast, with more continental influence and stronger dry-season effects. It still belongs to the tropical savanna family, but the rainy season is more concentrated and the dry season can feel longer and harsher. Residents should expect very warm afternoons, dusty harmattan conditions in winter, and a higher need for water planning than in the western coastal belt. This region is best for people who can handle heat and seasonal variability.

Summer:28-33°C

Winter:22-25°C

Moderate rainfall

Hotter and somewhat drier than the coast, with a strong wet season and a dusty, dry winter that can feel noticeably harsher.

Guinea-Bissau is a small country with limited climate diversity, so three zones capture it well: a wetter humid coast, a central agricultural belt, and a hotter, drier eastern interior. For residents and expats, the main appeal is year-round warmth, but practical life is strongly shaped by the long rainy season, high humidity, flooding risk in lowlands, and the dry harmattan months.

More Insights for your Move to Guinea-Bissau

Comprehensive guides and data-driven analysis.

View all Guinea-Bissau Guides & Categories14 in-depth guides for expats & digital nomads